• ahaas's avatar
    [turbofan] Implement rounding of floats on x64 and ia32 without sse4.1. · fa5d09e5
    ahaas authored
    The implementation sets the rounding mode flag and then uses the
    cvtsd2si and cvtsi2sd instructions (convert between float and int) to do
    the rounding. Input values outside int range either don't have to be
    rounded anyways, or are rounded by calculating input + 2^52 - 2^52 for
    positive inputs, or input -2^52 + 2^52 for negative inputs. The original
    rounding mode is restored afterwards.
    
    R=titzer@chromium.org
    
    B=575379
    
    Review URL: https://codereview.chromium.org/1584663007
    
    Cr-Commit-Position: refs/heads/master@{#33367}
    fa5d09e5
value-helper.h 10.8 KB